The present invention relates to rinse aid surface coatings, compositions, methods and articles of manufacture comprising a nanoparticle system or employing the same to impart surface modifying benefits for all types of dishware surfaces in automatic dishwashing applications.
The use of non-photoactive nanoparticles allows for the creation of rinse aid surface coatings, compositions, methods and articles of manufacture that create multi-use benefits to modified dishware surfaces. These surface modifications can produce durable, protective, long lasting or semi-permanent multi-use benefits that include at least one of the following improved surface properties: wetting and sheeting, uniform drying, anti-spotting, anti-staining, anti-filming, self cleaning, and durability, relative to dishware surfaces unmodified with such nanoparticle systems.
There have been many problems associated with developing rinse aid surface coatings for dishware that provide a beneficial layer with the desirable properties and which minimize the disadvantages, such as a limit to single use protection, insufficient coverage, roughness and/or flaking of coating during use, or in contrast, the inability to remove once applied (when a more temporary coating is desired) and a limit on surfaces that can be modified.
Current approaches to solving the coating problem includes the use of non-dispersive, film-forming polymer coatings and clay-containing, non-dispersive, film-forming polymer coatings. However, the substantivity of the non-dispersive, film-forming polymers (e.g. alkoxylated silicones, poly(N-vinyl-2-pyrrolidones, poly(N-vinyl-imidazoles, diblock copolymers of poly(ethylene oxide) and poly(lactide)) is poor such that its wetting/sheeting effect is short-lived, with spotting/residue negatives returning within 1-2 rinse cycles. Elevating the levels of non-dispersive polymers is not the solution to this problem. This is especially evident on dishware where elevated levels of polymers result in unacceptable residue or film problems. In the case of clay-containing, non-dispersive, film-forming polymer coatings, the nanoparticles are rheology agents for the formulations and do not themselves impart the benefit disclosed.
It is apparent that there is a continuing need to improve the various properties of all dishware surfaces in automatic dishwashers, including but not limited to plastics, metals, glass, wood and stone surfaces, via a dispersive coating composition and method of use which would result in dishware surfaces having one or more of the following highly desirable modified surface properties such as improved wetting and sheeting, uniform drying, anti-spotting, anti-staining, anti-filming, self cleaning, and durability. There is also a continuing need that these modified surface benefits be made the more responsive to consumer applications.
Additional background patents and patent publications, some of which disclose various uses of nanoparticles, include: U.S. Pat. Nos. 4,591,499 and 4,597,886; JP 04-353438; U.S. Pat. No. 5,429,867; JP 96053558; GB 2 303 373; U.S. Pat. No. 5,853,809; PCT WO 99/00457; WO 00/000554 A1; WO 01/27236; and WO 01/32820.
The present invention relates to rinse aid materials, coatings, compositions, methods, and articles of manufacture that provide some important dishware surface multi-use benefits that can be made durable, protective, long lasting or semi-permanent in the automatic dishwasher environment. These multi-use benefits include at least one of the following: improved wetting and sheeting, uniform drying, anti-spotting, anti-staining, anti-filming, self cleaning, and durability relative to surfaces that are not treated with the rinse aid materials, coatings, or coating compositions. The rinse aid surface coating composition of the present invention can be used in the automatic dishwashing cycle in conjunction with a general detergent or actually as a rinse aid in the rinsing or pre-drying cycle. The following are some non-limiting embodiments of the present invention.
In one embodiment of the present invention there is provided a rinse aid material for coating the dishware surfaces. As used herein, the term xe2x80x9ccoatingxe2x80x9d includes coatings that completely cover a surface, or portion thereof, as well as coatings that may only partially cover a surface, such as those coatings that after drying leave gaps in coverage on a surface. The latter category of coatings may include, but is not limited to a network of covered and uncovered portions (e.g., non-continuous covered regions of the surface). When the coatings described herein are described as being applied to a surface, it is understood that the coatings need not be applied to, or that they cover the entire surface. For instance, the coatings will be considered as being applied to a surface even if they are only applied to modify a portion of the surface.
As used herein, the term xe2x80x9ccoatingxe2x80x9d includes coatings that completely cover a surface, or portion thereof, as well as coatings that may only partially cover a surface, such as those coatings that after drying leave gaps in coverage on a surface. The latter category of coatings may include, but is not limited to a network of covered and uncovered portions (e.g., non-continuous covered regions of the surface). When the coatings described herein are described as being applied to a surface, it is understood that the coatings need not be applied to, or that they cover the entire surface. For instance, the coatings will be considered as being applied to a surface even if they are only applied to modify a portion of the surface. The rinse aid material for coating the dishware surfaces can comprise a plurality of non-photoactive nanoparticles, or it can comprise a single non-photoactive nanoparticle surface coating composition. Such a coating composition may comprise: (a) an effective amount of non-photoactive nanoparticles; (b) a dispersant polymer; (c) optionally a surfactant; Cd) optionally having associated to said nanoparticle surface a quantity of one or more functionalized surface molecules exhibiting properties selected from the group consisting of hydrophilic, hydrophobic and mixtures thereof; (e) optionally one or more adjunct ingredients; and (f) optionally a suitable carrier medium.
In another embodiment of the present invention, there is provided a method of applying a substantially clear coating to a dishware surface during the rinse cycle of an automatic dishwashing appliance comprising: applying a material comprising an effective amount of non-photoactive nanoparticles to the dishware surface; and, actively curing the material to form a coating on the dishware surface.
In another embodiment of the present invention, there may be provided a rinse aid surface coating composition for coating the dishware surfaces comprising (a) an effective amount of non-photoactive nanoparticles; (b) a dispersant polymer selected from the group consisting of polyacrylic acid, poly (acrylic/allyl alcohol), poly (acrylic/maleic), polycarboxylic acids, sodium tripolyphosphate, pyrophosphate, and mixtures thereof; (c) optionally a surfactant; (d) optionally having associated to said nanoparticle surface a quantity of one or more functionalized surface molecules exhibiting properties selected from the group consisting of hydrophilic, hydrophobic and mixtures thereof; (e) optionally one or more adjunct ingredients; and (f) optionally a suitable carrier medium.
In another embodiment of the present invention, there may be provided a rinse aid surface coating composition for coating the dishware surfaces comprising (a) an effective amount of non-photoactive nanoparticles wherein the non-phocoactive nanoparticles are selected from the group consisting of LAPONITE RD(trademark) and LAPONITE BT(trademark), and mixtures thereof; (b) a dispersant polymer selected from the group consisting of polyacrylic acid, poly (acrylic/allyl alcohol), poly (acrylic/maleic), polycarboxylic adds, sodium tripolyphosphate, pyrophosphate, and mixtures thereof; (c) optionally a surfactant; (d) optionally having associated to said nanoparticle surface a quantity of one or more functionalized surface molecules exhibiting properties selected from the group consisting of hydrophilic, hydrophobic and mixtures thereof; (e) optionally one or more adjunct ingredients; and (f) optionally a suitable carrier medium.
One embodiment of this invention uses LAPONITE XLS(trademark) having the following characteristics: analysis (dry basis) SiO2 59.8%, MgO 27.2%, Na2O 4.4%, Li2O 0.8%, structural H2O 7.8%, with the addition of tetrasodium pyrophosphate (6%); specific gravity 2.53; bulk density 1.0.
In another embodiment of the present invention, there may be provided a rinse aid surface coating composition for coating the dishware surfaces comprising (a) an effective amount of non-photoactive nanoparticles wherein the non-photoactive nanoparticles are selected from the group consisting of LAPONITE RD(trademark) and LAPONITE B(trademark), and mixtures thereof; (b) a dispersant polymer selected from the group consisting of polyacrylic acid, poly (acrylic/ally alcohol), poly (acrylic/maleic), polycarboxylic acids, sodium tripolyphosphate, pyrophosphate, and mixtures thereof; (c) optionally a surfactant; (d) optionally having associated to said nanoparticle surface a quantity of one or more functionalized surface molecules exhibiting properties selected from the group consisting of hydrophilic, hydrophobic and mixtures thereof; (e) optionally one or more adjunct ingredients; and (f) optionally a suitable carrier medium.
In another embodiment of the present invention there may be provided a method of using a rinse aid surface coating composition by (a) mixing said nanoparticles in suitable carrier medium to form said surface coating composition; (b) mixing said nanoparticles dispersed in suitable carrier medium with a dispersant polymer to inhibit gel formation; (c) optionally mixing said nanoparticles dispersed in suitable carrier medium with a dispersant polymer and adjunct ingredients to form said surface coating composition; (d) optionally mixing said nanoparticles dispersed in suitable carrier medium with a dispersant polymer and a surfactant to form said surface coating composition; (e) optionally mixing said nanoparticles dispersed in suitable carrier medium with a dispersant polymer and a pH-adjusting agent to form said surface coating composition; (f) optionally mixing said nanoparticles dispersed in suitable carrier medium with a dispersant polymer, adjunct ingredients and surfactant to form said surface coating composition; (g) optionally mixing said nanoparticles dispersed in suitable carrier medium with a dispersant, a surfactant, a pH-adjusting agent and adjunct ingredients to form said surface coating composition; (h) applying said surface coating composition to a dishware surface; (i) allowing said surface coating composition to dry, or drying the rinse aid surface coating composition; and (j) optionally repeating any of steps (a) through (i) as needed.
The drying step can comprise air drying in ambient conditions, or it can comprise actively drying the rinse aid surface coating composition by utilizing any technology known for accelerating the drying process (such as, in the drying cycle of an automatic dishwashing appliance). It has been found the heat drying the rinse aid surface coating composition can greatly increase the durability of the dishware surface coating.
In another embodiment of the present invention there may be provided an article of manufacture comprising an applicator, such as an automatic dishwashing appliance spray dispenser, a spray dispenser, an immersion container, a hose spray dispenser attachment, a fabric or a porous article, such as a sponge; further comprising (a) a dishware coating composition, wherein said surface coating composition may be in the physical form selected from the group consisting of liquid, liquid concentrate, gel, powder, tablet, granule and mixtures thereof; (b) optionally a source of water or deionized water; and (c) optionally a set of instructions in association with said spray dispenser comprising an instruction to dispense said surface coating composition from said spray dispenser onto said dishware surface.
In another embodiment of the present invention there may be provided a treated dishware surface coated with the rinse aid surface coating composition. Substrates treated with the benefit agent materials of the present invention exhibit a greater improvement in wetting and sheeting, uniform drying, anti-spotting, anti-staining, staining, anti-filming, self cleaning, and durability than substrates treated without such benefit agent materials.
In another embodiment of the invention there may be provided a treated dishware surface coated with a rinse aid surface coating composition, where the rinse aid surface coating composition may be strippable. Substrates treated with the benefit agent materials of the present invention exhibit a greater improvement in wetting and sheeting, uniform drying, anti-spotting, anti-staining, staining, anti-filming, self cleaning, and durability after at least one effective nanoparticle layer has been stripped than substrates treated without such benefit agent materials.
Numerous other embodiments are also possible. These elements of the embodiments described herein can also be combined in other ways, or with other elements to create still further embodiments.
All percentages, ratios and proportions herein are on a weight basis based on a neat product unless otherwise indicated. All documents cited herein are hereby incorporated by reference.